Topband: narrow filters on 160m

[jim.thom jim.thom@telus.net]

On 2/7/2026 5:18 PM, JC(Jose Carlos) via Topband wrote:
> the CW speaker is not a filter with group delay that causes the ring
sound.

>Ringing is the result of phase shift produced by filter skirts, and is
>excited by noise, and how much is produced depends on curve shaping.

>73, Jim

When 160m is really noisy,  when the narrow 500/250/125 hz xtal filters are
used, the noise...'rings out" the filters.   W8JI mentioned the same effect
years ago.
160m is frustrating at the best of times.

Jim  VE7RF